Effects of intravascular low-level laser therapy during coronary intervention on selected growth factors levels

The objective of this study was to evaluate the effect of intravascular low-level laser therapy (LLLT) on selected growth factor levels in subjects undergoing percutaneous coronary interventions (PCI).

Restenosis remains the main problem with the long-term efficacy of PCI, and growth factors are postulated to play a crucial role in the restenosis cascade.

In a randomized prospective study, an 808 nm LLLT (100 mW/cm2, continuous wave laser, 9 J/cm2, illuminated area 1.6-2.5 cm2) was delivered intracoronarily to patients during PCI. Fifty-two patients underwent irradiation with laser light, and 49 constituted the control group. In all individuals, serum levels of insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), transforming growth factor-β1 (TGF-β1), and fibroblast growth factor-2 (FGF-2) were measured before angioplasty, then 6 and 12 h and 1 month after the procedure. In all patients, a control angiography was performed 6 months later.

There were no significant differences in IGF-1 and VEGF levels between the groups. While evaluating FGF-2, we observed its significantly lower levels in the irradiated patients during each examination. There was a significant increase in TGF-β1 level in control group after 12 h of observation. In the irradiated individuals, control angiography revealed smaller late lumen loss and smaller late lumen loss index as compared with the control group. The restenosis rate was 15.0% in the treated group, and 32.4% in the control group, respectively.

LLLT decreases levels of TGF-β1 and FGF-2 in patients undergoing coronary intervention, which may explain smaller neointima formation.